Providing rapid intermittent compression (IC) therapy to persons with dysvascular amputation should reduce the number of reamputations that are performed by increasing blood flow to the residual limb. Increasing perfusion of the limb will both limit ulcer formation and promote ulcer healing. Patient compliance has been shown to be important to successful outcomes with IC therapy. Therefore, this project's long-term objective is to develop a rapid IC device that can be integrated into a prosthetic socket. Integrating the compression device into the socket will allow users to receive IC therapy without being confined to a chair for six hours a day and will thus increase patient compliance and enable the therapy to be performed in a preventative manner. Reducing the number of reamputations would maintain the quality of life of the patient by halting further limb loss, which has a negative impact on a number of functional and psychosocial variables. In addition, postoperative morbidities are caused by the underlying disease in half of major amputations and operative mortality rates as high as 17% have been reported. Finally, it has been calculated that $1.7 billion is spent annually on reamputation procedures performed on trans-tibial and trans-femoral amputees. By reducing the prevalence of reamputation though IC therapy we hope to improve the patient's quality of life and meet NIH's mission of improving human health through biomedical research. The objective of this project is to determine the feasibility of developing an actuator that can both mimic current commercial devices and be integrated into a prosthetic socket. One aim of the project is to develop an actuator that is capable of producing pressures similar to those that are created in current commercial devices while adhering to weight and power consumption requirements. To meet this goal we plan to investigate the use of electro-active polymers (EAPs) as they are light in weight, responsive, use little power and have a high energy density. Another aim is to develop an artificial residual limb that is instrumented with pressure sensors. The mock residual limb will allow us to quantify the pressures that are applied to the residual limb by both current commercial systems as well as the device that will be developed under this effort. This instrumented limb will likely use commercial-off the- shelf sensor technology to enable rapid design iterations without placing human subjects at risk during the development process. The final aim is to work with local prosthetics to integrate the actuator into a prosthetic socket and use the instrumented artificial limb to ensure that we meet our pressure, weight and power consumption goals. PUBLIC HEALTH RELEVANCE: The purpose of this project is to develop a device that provides rapid intermittent compression to the residual limb of amputees that do not have good blood flow in their limbs. The device will be built into the prosthetic socket to provide the user with portable therapy throughout the day, which will free the user from being confined to a chair for up to six hours each day to receive suggested amount of therapy. This device will reduce the number of ulcers that form, help those ulcers that do form to heal and will reduce the number of reamputation surgeries that need to occur by increasing blood flow in the limb, which will not only help to reduce the $1.7 billion that is spent each year in the United States related to but also improve the quality of life of amputees by maintaining their functional status and not requiring them to undergo further surgery.